Background: Unless President Obama reverses course, oil drilling will begin in the pristine Arctic Ocean this summer — opening this fragile home of polar bears, walrus, seals and native communities to dangerous new oil exploration and our rapidly warming climate to even more global warming pollution.

President Obama has already given tentative approval to Shell's Arctic drilling plan, but citizens and “Frostpaw” the polar bear plan to use Obama’s visit to San Francisco on Thursday to ask him to stop Shell from drilling in the Arctic.